From: Prasad J Pandit <p...@fedoraproject.org> While performing mmio device r/w operations, guest could set 'addr' parameter such that 'locty' index exceeds TPM_TIS_NUM_LOCALITIES=5 after setting new 'locty' via 'tpm_tis_new_active_locality'. Add check to avoid OOB access.
Reported-by: Cheng Feng <ps...@huawei.com> Signed-off-by: Prasad J Pandit <p...@fedoraproject.org> --- hw/tpm/tpm_tis.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) Update: add assert() calls -> https://lists.gnu.org/archive/html/qemu-devel/2018-11/msg00912.html diff --git a/hw/tpm/tpm_tis.c b/hw/tpm/tpm_tis.c index 12f5c9a759..d6bf3ceb26 100644 --- a/hw/tpm/tpm_tis.c +++ b/hw/tpm/tpm_tis.c @@ -293,6 +293,7 @@ static void tpm_tis_request_completed(TPMIf *ti, int ret) uint8_t locty = s->cmd.locty; uint8_t l; + assert(TPM_TIS_IS_VALID_LOCTY(locty)); if (s->cmd.selftest_done) { for (l = 0; l < TPM_TIS_NUM_LOCALITIES; l++) { s->loc[locty].sts |= TPM_TIS_STS_SELFTEST_DONE; @@ -401,6 +402,7 @@ static uint64_t tpm_tis_mmio_read(void *opaque, hwaddr addr, uint32_t avail; uint8_t v; + assert(TPM_TIS_IS_VALID_LOCTY(locty)); if (tpm_backend_had_startup_error(s->be_driver)) { return 0; } @@ -523,6 +525,7 @@ static void tpm_tis_mmio_write(void *opaque, hwaddr addr, uint16_t len; uint32_t mask = (size == 1) ? 0xff : ((size == 2) ? 0xffff : ~0); + assert(TPM_TIS_IS_VALID_LOCTY(locty)); trace_tpm_tis_mmio_write(size, addr, val); if (locty == 4) { @@ -642,7 +645,7 @@ static void tpm_tis_mmio_write(void *opaque, hwaddr addr, } } - if (set_new_locty) { + if (set_new_locty && TPM_TIS_IS_VALID_LOCTY(active_locty)) { tpm_tis_new_active_locality(s, active_locty); } -- 2.17.2
